Process of hardening and tempering steel.



State of Oregon,

steel the same is B ARNABAS J. OASTE-RLINE, OF PORTLAND, OREGON,

PATENT OFFICE.

ASSIGNOR TO CASTERLINE OUTLERY COMPANY, OF PORTLANROREGON, ACORPORATION.

- RocEss OF HARDENING AND TEMPERING STEEL.

Specification of Letters Patent;

Patented Feb. 18, 1908.

Application filed June 13 1907. Serial No. 378.728,

To alZ'whom it magi concern:

Be it known that I, BARNABAS J. CASTER- ILIN'EL, a citizen of the UnitedStates, and resident-of Portland, county ofMultnomah, and have inventedcertain new and useful Im rovements. in Processes of Hardening and ifollowing 1s' a specifi c'ati on..

' This invention relates. to a process of bar- .dening and'tem eringsteel especially such artic lescompose all edged-tools. {The objeots ofthe invention being to prevent crystallization;-to attain a maximumdegree silvery-a pearance; to obviate the necessity ofildepen mg uponnatural elements such as air and water, or upon quicksilver, salammonlac'and alum; to produce anot onlyexcessively hard, but exceedinglymalleable product which has qualities of'resistance enabl ing. the sameto be successfully employed as a, means steel or chromium steel; and torovi'de articles of' the character named which embody elements of greatdurability. These objects are attained'in my improved v ploying. asolution of salt, saltpeter, wood alcohol, carbonate of iron, borax,glycerin and oil. I

To. temper and harden a given "article of first heated to a cherryredheat, then immersed into the above named solution-and kept submerged forthe same length of time required to allow water to subside anddiscontinue bubbling when a piece-of cherry-red heated steel is submeredtherein; said period of time will be readll understood by thosefamiliar-with the art 0 tempering metals. v After being allowed to-coolin the solution for a period as stated above the article is coated withtallow and then heated slowly by holding it over a slow fire, untildrawn to the degree of mallea empering Steel, of which the of'steel asdrills, blades and of hardness and a white,-

for cutting and drilling manganese process by emany perceptible mannerheat, then submerging then coating the steel bility' required, theperiod of time being va ried according to the uses for which the articlebeing tempered is intended.

In the operation and use of my invention sharp-edged knives tempered bythe said process may be readily employed to alternately out chips from asteel bar and shave fine hair from the back of a human hand withoutperceptible dulling of the edge; drills so tempered may be employed fordrilling holes through hard steel Without in impairing their cuttingedges; edge tools of all character. are made very durable and maintainedin perfect working shape for a maximum length of time, and elongatedcutting blades such as swords may edges not susceptible of being dentedor turned by contact with other blades, while at the same time the blademay embody the desirable degree ofresiliency.

Having'thus described my invention, what I claim as new, and desire tosecure by Let'- ters Patent, is

The hereinbefore described improvement in tempering and hardening steel,consisting of first heating the steel to a cherry red and cooling thesteel in a solution ofsalt, salt eter, carbonate of iron, borax, woodalcoho i, glycerin and oil;

jecting it to mg it over scribed.

. *In testimony that, I claim the foregoing as the same, substantiallyas demy invention, I have signed my name 1n resence of two Witnesses,this 24th day of lay 19.07;

BARNABAS J. OASTERLINE'.

Witnesses:

W. JUNrs,

FRANK Mo'r'rEn.

be provided with exceedingly keen,

-with tallow', and s11b the action of a slow fire by hold--

